diff --git a/apps/desktop/e2e/live-backlog.spec.ts b/apps/desktop/e2e/live-backlog.spec.ts
index 4362ea2..b610aac 100644
--- a/apps/desktop/e2e/live-backlog.spec.ts
+++ b/apps/desktop/e2e/live-backlog.spec.ts
@@ -11,6 +11,7 @@ const MAIN = join(here, '..', 'out', 'main', 'index.js')
 test.describe('live backlog', () => {
   test('The pot + Focus render real gitea data', async () => {
     test.skip(!process.env.GITEA_LIVE, 'GITEA_LIVE not set — opt-in live test')
+    test.setTimeout(90_000)
     const app = await electron.launch({ args: [MAIN], env: { ...process.env } })
     const win = await app.firstWindow()
     await win.waitForLoadState('domcontentloaded')
@@ -42,16 +43,17 @@ test.describe('live backlog', () => {
       win.getByText(/cold-start priors · \d+\/20 closed issues estimated|calibrated on \d+ closed/),
     ).toBeVisible()
     // Real per-milestone forecasts — these milestone names come from gitea, not the
-    // fixture (which lists Beta / Pilot-ready / v1.0).
-    await expect(win.getByText(/P2 — Scheduler/)).toBeVisible()
+    // fixture (Beta / Pilot-ready / v1.0). The runway shows milestones with open
+    // scope; P5 is active (P2 is fully shipped, so it's correctly omitted).
+    await expect(win.getByText(/P5 — Dogfood/)).toBeVisible()
     // Real capacity config from pm-state (christian/stephen), not the fixture (Stephen/Ana K.)
     await expect(win.getByText('christian', { exact: true })).toBeVisible()
     await expect(win.getByText(/pd\/day/).first()).toBeVisible()
     await win.screenshot({ path: join(here, '.artifacts', 'screens', 'live-runway.png'), fullPage: true, animations: 'disabled' })
 
-    // Milestone drill-in — clicking a real milestone opens its real detail
-    await win.getByText(/P2 — Scheduler/).click()
-    await expect(win.getByRole('heading', { name: 'P2 — Scheduler + Monte Carlo' })).toBeVisible()
+    // Milestone drill-in — clicking a real (active) milestone opens its real detail
+    await win.getByText(/P5 — Dogfood/).click()
+    await expect(win.getByRole('heading', { name: 'P5 — Dogfood + polish' })).toBeVisible()
     await expect(win.getByText(/\d+ issues · est \d+d/)).toBeVisible()
     await win.screenshot({ path: join(here, '.artifacts', 'screens', 'live-milestone.png'), fullPage: true, animations: 'disabled' })
     await rail.getByRole('button', { name: 'Runway' }).click()
@@ -68,10 +70,15 @@ test.describe('live backlog', () => {
     await win.getByRole('main').getByRole('link').first().click()
     await expect(win.getByText(/· stephen\/commitea/)).toBeVisible()
     await win.getByRole('button', { name: 'Adjust' }).click()
-    await expect(win.getByText('Adjust estimate & priority')).toBeVisible()
+    await expect(win.getByText('Adjust issue')).toBeVisible()
     await win.getByRole('combobox').first().selectOption('est/8d')
-    await expect(win.getByText('Proposed label change')).toBeVisible()
+    await expect(win.getByText('Proposed change')).toBeVisible()
     await expect(win.getByText(/est\/8d/).last()).toBeVisible()
+    // the unified tool also drives assignee + milestone — the pickers render and diff
+    await expect(win.getByText('Assignee', { exact: true })).toBeVisible()
+    await expect(win.getByText('Milestone', { exact: true })).toBeVisible()
+    await win.getByRole('combobox').nth(2).selectOption('') // Assignee → Unassigned
+    await expect(win.getByText('unassign', { exact: true })).toBeVisible()
     await win.screenshot({ path: join(here, '.artifacts', 'screens', 'live-apply-change.png'), fullPage: true, animations: 'disabled' })
     await win.getByRole('button', { name: 'Cancel' }).click() // no mutation
 
diff --git a/apps/desktop/src/main/gitea.ts b/apps/desktop/src/main/gitea.ts
index b7d3224..1bafee0 100644
--- a/apps/desktop/src/main/gitea.ts
+++ b/apps/desktop/src/main/gitea.ts
@@ -333,6 +333,17 @@ export function registerGiteaIpc(): void {
     }
   })
 
+  // Assignable people (repo collaborators) for the Adjust dialog's assignee picker.
+  ipcMain.handle('gitea:collaborators', async () => {
+    const client = getGiteaClient()
+    if (!client) return []
+    try {
+      return await client.listCollaborators()
+    } catch {
+      return []
+    }
+  })
+
   // ---- config (team onboarding) ----
   ipcMain.handle('config:get', () => publicConfig())
 
diff --git a/apps/desktop/src/main/model.ts b/apps/desktop/src/main/model.ts
index a4c7711..7883448 100644
--- a/apps/desktop/src/main/model.ts
+++ b/apps/desktop/src/main/model.ts
@@ -13,7 +13,6 @@ import {
   type ChangeProposal,
   type ChatMessage,
   createChatClient,
-  describeChange,
   type ModelRouter,
   type ProjectView,
   proposalsFor,
@@ -130,10 +129,19 @@ export function registerModelIpc(): void {
         const a = (args ?? {}) as ProposeChangeArgs
         const issue = await client.getIssue(a.issue).catch(() => null)
         if (!issue) return { error: `issue #${a.issue} not found` }
-        const built = proposalsFor(a, issue.labels, issue.title)
+        // Milestone titles + current assignee/milestone let a proposal label the
+        // milestone and skip a no-op assign/move.
+        const milestones = (a.milestone !== undefined ? await client.listMilestones().catch(() => []) : []).map(
+          (m) => ({ id: m.id, title: m.title }),
+        )
+        const built = proposalsFor(a, issue.labels, issue.title, {
+          currentAssignee: issue.assignee,
+          currentMilestoneId: issue.milestone?.id ?? null,
+          milestones,
+        })
         proposals.push(...built)
         return built.length
-          ? { proposed: built.map((p) => ({ issue: a.issue, diff: describeChange(p.plan) })) }
+          ? { proposed: built.map((p) => ({ issue: a.issue, diff: p.summary })) }
           : { proposed: [], note: 'no change — already at that value' }
       }
       if (name === 'record_directive') {
diff --git a/apps/desktop/src/preload/index.ts b/apps/desktop/src/preload/index.ts
index cd8c2c9..b780fee 100644
--- a/apps/desktop/src/preload/index.ts
+++ b/apps/desktop/src/preload/index.ts
@@ -15,6 +15,8 @@ const api = {
     applyChange: (change: unknown) => ipcRenderer.invoke('gitea:applyChange', change),
     /** File a set of captured issues with their est/* + p/* labels. */
     createIssues: (issues: unknown) => ipcRenderer.invoke('gitea:createIssues', issues),
+    /** Assignable people (repo collaborators) for the assignee picker. */
+    collaborators: () => ipcRenderer.invoke('gitea:collaborators'),
   },
   pmstate: {
     /** Read the directive ledger from the pm-state repo. */
diff --git a/apps/desktop/src/renderer/src/components/screens/issue-screen.tsx b/apps/desktop/src/renderer/src/components/screens/issue-screen.tsx
index a8cc758..acbae4a 100644
--- a/apps/desktop/src/renderer/src/components/screens/issue-screen.tsx
+++ b/apps/desktop/src/renderer/src/components/screens/issue-screen.tsx
@@ -21,12 +21,20 @@ export function IssueScreen({
   onOpenIssue,
   canWrite = false,
   onApplyChange,
+  collaborators = [],
+  milestones = [],
+  currentAssignee = null,
+  currentMilestoneId = null,
 }: {
   issue: IssueRef
   onBack: () => void
   onOpenIssue: (issue: IssueRef) => void
   canWrite?: boolean
   onApplyChange?: (change: IssueChange) => Promise<{ ok: boolean }>
+  collaborators?: { login: string; name: string }[]
+  milestones?: { id: number; title: string }[]
+  currentAssignee?: string | null
+  currentMilestoneId?: number | null
 }) {
   const det: IssueDetail = ISSUE_DETAIL[issue.id] || {
     state: 'triage',
@@ -59,23 +67,38 @@ export function IssueScreen({
   const labels = issue.labels ?? []
   const curEstimate = labels.find((l) => l.startsWith('est/')) ?? ''
   const curPriority = labels.find((l) => l.startsWith('p/')) ?? ''
+  const curAssignee = currentAssignee ?? ''
+  const curMilestone = currentMilestoneId != null ? String(currentMilestoneId) : ''
   const [adjustOpen, setAdjustOpen] = useState(false)
   const [estimate, setEstimate] = useState(curEstimate)
   const [priority, setPriority] = useState(curPriority)
+  const [assignee, setAssignee] = useState(curAssignee)
+  const [milestone, setMilestone] = useState(curMilestone)
   const [applying, setApplying] = useState(false)
 
   const openAdjust = () => {
     setEstimate(curEstimate)
     setPriority(curPriority)
+    setAssignee(curAssignee)
+    setMilestone(curMilestone)
     setAdjustOpen(true)
   }
 
-  // the concrete changes this dialog would apply, one per axis that differs
+  // the concrete changes this dialog would apply, one per field that differs
   const pendingChanges: IssueChange[] = []
   if (estimate !== curEstimate)
     pendingChanges.push({ kind: 'reestimate', issue: issue.id, estimate: (estimate || null) as EstimateLabel | null })
   if (priority !== curPriority)
     pendingChanges.push({ kind: 'reprioritize', issue: issue.id, priority: (priority || null) as PriorityLabel | null })
+  if (assignee !== curAssignee)
+    pendingChanges.push({ kind: 'assign', issue: issue.id, assignee: assignee || null })
+  if (milestone !== curMilestone)
+    pendingChanges.push({
+      kind: 'remilestone',
+      issue: issue.id,
+      milestone: milestone ? Number(milestone) : null,
+      milestoneTitle: milestones.find((m) => String(m.id) === milestone)?.title ?? null,
+    })
 
   const diffs = pendingChanges.map((c) => summarizeChange(c, labels))
 
@@ -92,6 +115,14 @@ export function IssueScreen({
 
   const estOptions = [{ value: '', label: NONE }, ...ESTIMATE_LABELS.map((l) => ({ value: l, label: l }))]
   const prioOptions = [{ value: '', label: NONE }, ...PRIORITY_LABELS.map((l) => ({ value: l, label: l }))]
+  const assigneeOptions = [
+    { value: '', label: 'Unassigned' },
+    ...collaborators.map((c) => ({ value: c.login, label: c.name })),
+  ]
+  const milestoneOptions = [
+    { value: '', label: NONE },
+    ...milestones.map((m) => ({ value: String(m.id), label: m.title })),
+  ]
 
   return (
     <div style={{ display: 'flex', flexDirection: 'column', gap: 16 }}>
@@ -132,7 +163,7 @@ export function IssueScreen({
       <Dialog
         open={adjustOpen}
         onClose={() => setAdjustOpen(false)}
-        title="Adjust estimate & priority"
+        title="Adjust issue"
         footer={
           <>
             <Button variant="ghost" onClick={() => setAdjustOpen(false)}>
@@ -158,15 +189,35 @@ export function IssueScreen({
             onChange={(e) => setPriority(e.target.value)}
           />
         </div>
+        {(collaborators.length > 0 || milestones.length > 0) && (
+          <div style={{ display: 'flex', gap: 14, marginTop: 12 }}>
+            {collaborators.length > 0 ? (
+              <Select
+                label="Assignee"
+                options={assigneeOptions}
+                value={assignee}
+                onChange={(e) => setAssignee(e.target.value)}
+              />
+            ) : null}
+            {milestones.length > 0 ? (
+              <Select
+                label="Milestone"
+                options={milestoneOptions}
+                value={milestone}
+                onChange={(e) => setMilestone(e.target.value)}
+              />
+            ) : null}
+          </div>
+        )}
         <div style={{ marginTop: 14, minHeight: 40 }}>
           {pendingChanges.length === 0 ? (
             <p style={{ font: 'var(--text-agent)', color: 'var(--ink-3)', margin: 0 }}>
-              No change yet — pick a different estimate or priority.
+              No change yet — pick a different estimate, priority, assignee, or milestone.
             </p>
           ) : (
             <>
               <p style={{ font: 'var(--text-overline)', letterSpacing: 'var(--letter-spacing-wide)', textTransform: 'uppercase', color: 'var(--ink-3)', margin: '0 0 6px' }}>
-                Proposed label change
+                Proposed change
               </p>
               {diffs.map((d) => (
                 <div key={d} style={{ font: '500 13px var(--font-mono)', color: 'var(--ink-1)' }}>
@@ -174,7 +225,7 @@ export function IssueScreen({
                 </div>
               ))}
               <p style={{ font: 'var(--text-agent)', color: 'var(--ink-2)', margin: '8px 0 0' }}>
-                Writes the label to gitea and re-runs the plan. Nothing else changes.
+                Writes to gitea and re-runs the plan. Nothing else changes.
               </p>
             </>
           )}
diff --git a/apps/desktop/src/renderer/src/components/shell/app-shell.tsx b/apps/desktop/src/renderer/src/components/shell/app-shell.tsx
index c7e8187..a81101d 100644
--- a/apps/desktop/src/renderer/src/components/shell/app-shell.tsx
+++ b/apps/desktop/src/renderer/src/components/shell/app-shell.tsx
@@ -101,6 +101,7 @@ export function AppShell() {
   const [milestoneId, setMilestoneId] = useState<number | null>(null)
   const [gate, setGate] = useState<'checking' | 'connect' | 'ready'>('checking')
   const [pubConfig, setPubConfig] = useState<PublicConfig | null>(null)
+  const [collaborators, setCollaborators] = useState<{ login: string; name: string }[]>([])
   const [backlog, refetchBacklog] = useBacklog()
   const capacityMembers = useCapacity()
   const workers = capacityWorkers(capacityMembers)
@@ -144,8 +145,17 @@ export function AppShell() {
       .then((s) => setGate(s.demo || s.configured ? 'ready' : 'connect'))
       .catch(() => setGate('connect'))
     window.commitea.config.get().then(setPubConfig).catch(() => {})
+    // Assignable people for the Adjust dialog's assignee picker (empty when demo/unconfigured).
+    window.commitea.gitea.collaborators().then(setCollaborators).catch(() => {})
   }, [])
 
+  // The open issue's current assignee + milestone (from the reconciled backlog),
+  // so the Adjust dialog can preselect and diff them. Milestones list feeds its picker.
+  const currentIssue =
+    backlog.status === 'ready' && issue ? backlog.issues.find((i) => i.number === issue.id) : undefined
+  const milestoneOptions =
+    backlog.status === 'ready' ? backlog.milestones.map((m) => ({ id: m.id, title: m.title })) : []
+
   const openIssue = (ref: IssueRef) => {
     if (view !== 'issue') setPrevView(view)
     setIssue(ref)
@@ -286,6 +296,10 @@ export function AppShell() {
             onOpenIssue={openIssue}
             canWrite={backlog.status === 'ready'}
             onApplyChange={applyChange}
+            collaborators={collaborators}
+            milestones={milestoneOptions}
+            currentAssignee={currentIssue?.assignee ?? null}
+            currentMilestoneId={currentIssue?.milestone?.id ?? null}
           />
         ) : null
       case 'states':
diff --git a/apps/desktop/src/renderer/src/components/shell/chat-panel.tsx b/apps/desktop/src/renderer/src/components/shell/chat-panel.tsx
index d396d13..f614251 100644
--- a/apps/desktop/src/renderer/src/components/shell/chat-panel.tsx
+++ b/apps/desktop/src/renderer/src/components/shell/chat-panel.tsx
@@ -1,6 +1,6 @@
 import React, { useEffect, useRef, useState } from 'react'
 
-import { describeChange, type IssueChange } from '@commitea/core'
+import type { IssueChange } from '@commitea/core'
 
 import { useChat } from '../../lib/use-chat.js'
 import { Button, Icon, IconButton } from '../ui/index.js'
@@ -127,7 +127,7 @@ export function ChatPanel({ onOpenDirectives, offline, onApplyChange }: ChatPane
             <div style={{ font: 'var(--text-caption)', color: 'var(--ink-3)', textTransform: 'uppercase', letterSpacing: 'var(--letter-spacing-wide)' }}>
               Proposed · #{p.change.issue}
             </div>
-            <div style={{ font: '500 13px var(--font-mono)', color: 'var(--ink-1)' }}>{describeChange(p.plan)}</div>
+            <div style={{ font: '500 13px var(--font-mono)', color: 'var(--ink-1)' }}>{p.summary}</div>
             <div style={{ display: 'flex', gap: 8 }}>
               <Button size="sm" onClick={() => approve(p)} disabled={offline}>
                 Approve
diff --git a/apps/desktop/src/renderer/src/global.d.ts b/apps/desktop/src/renderer/src/global.d.ts
index c5e01db..50736bd 100644
--- a/apps/desktop/src/renderer/src/global.d.ts
+++ b/apps/desktop/src/renderer/src/global.d.ts
@@ -86,6 +86,7 @@ export interface GiteaBridge {
   getIssue(index: number): Promise<GiteaIssue | null>
   applyChange(change: IssueChange): Promise<ApplyChangeResult>
   createIssues(issues: ProposedIssue[]): Promise<CreateIssuesResult>
+  collaborators(): Promise<{ login: string; name: string }[]>
 }
 
 /** One agent turn's result. */
diff --git a/apps/desktop/src/renderer/src/lib/use-chat.ts b/apps/desktop/src/renderer/src/lib/use-chat.ts
index dec3353..95a4fa7 100644
--- a/apps/desktop/src/renderer/src/lib/use-chat.ts
+++ b/apps/desktop/src/renderer/src/lib/use-chat.ts
@@ -133,14 +133,13 @@ export function useChat(onApplyChange?: (change: IssueChange) => Promise<{ ok: b
     (p: ChangeProposal) => {
       if (!onApplyChange) return
       drop(p)
-      const label = p.plan.added[0] ?? p.plan.removed[0] ?? 'change'
       void onApplyChange(p.change).then((res) => {
         setConvo((c) => [
           ...c,
           {
             from: 'agent',
             text: res.ok
-              ? `Done — #${p.change.issue} is now ${label}. The plan's been re-run.`
+              ? `Done — #${p.change.issue}: ${p.summary}. The plan's been re-run.`
               : `That didn't take — #${p.change.issue} is unchanged.`,
           },
         ])
diff --git a/packages/core/src/agent/agent-tools.ts b/packages/core/src/agent/agent-tools.ts
index f6fd4c7..7d05c0c 100644
--- a/packages/core/src/agent/agent-tools.ts
+++ b/packages/core/src/agent/agent-tools.ts
@@ -38,15 +38,19 @@ export const QUERY_PROJECT_TOOL: ToolDecl = {
 export const PROPOSE_CHANGE_TOOL: ToolDecl = {
   name: 'propose_change',
   description:
-    "Propose an estimate and/or priority change to an issue. This does NOT apply anything — it shows the " +
-    'human a diff to approve. Use it whenever the user asks to re-estimate or reprioritize. After calling it, ' +
-    "tell the user you've *proposed* the change for approval — never say it is done.",
+    'Propose a change to an issue — estimate, priority, assignee, and/or milestone. This does NOT apply ' +
+    'anything; it shows the human a diff to approve. Use it whenever the user asks to re-estimate, reprioritize, ' +
+    'assign someone (or unassign), or move an issue to a milestone. Pass a login for `assignee` (null to ' +
+    'unassign) and a milestone id for `milestone` (null to remove). After calling it, tell the user you have ' +
+    '*proposed* the change for approval — never say it is done.',
   parameters: {
     type: 'object',
     properties: {
       issue: { type: 'number', description: 'the issue number to change' },
       estimate: { type: 'string', enum: ['est/1d', 'est/2d', 'est/3d', 'est/5d', 'est/8d'] },
       priority: { type: 'string', enum: ['p/1', 'p/2', 'p/3', 'p/4'] },
+      assignee: { type: 'string', description: 'gitea login to assign, or null to unassign' },
+      milestone: { type: 'number', description: 'milestone id to set, or null to remove from its milestone' },
     },
     required: ['issue'],
   },
@@ -84,7 +88,7 @@ export const REGINALD_SYSTEM = [
   'You are Reginald, the calm, dry project manager inside CommiTea — a tool that runs projects on Gitea.',
   'Call query_project to ground every answer in the real project; never invent issues, numbers, or dates.',
   'The scheduler and forecasts are deterministic code — report their output, do not recompute it.',
-  'To change an estimate or priority, call propose_change — it shows the human a diff to approve.',
+  'To change an estimate, priority, assignee, or milestone, call propose_change — it shows the human a diff to approve.',
   'When the PM states standing intent ("pilots first", "freeze scope"), call record_directive to log it.',
   'Never claim a change is applied; you propose, the human approves. Forecasts are ranges, never single dates.',
   'Refer to issues as #<number>. Be brief and plain — a sentence or two. No preamble, no bullet dumps.',
diff --git a/packages/core/src/changes/apply-changes-v0.test.ts b/packages/core/src/changes/apply-changes-v0.test.ts
index 7661fd3..4c15dd7 100644
--- a/packages/core/src/changes/apply-changes-v0.test.ts
+++ b/packages/core/src/changes/apply-changes-v0.test.ts
@@ -65,11 +65,31 @@ describe('proposalsFor', () => {
     const props = proposalsFor({ issue: 2, estimate: 'est/5d', priority: 'p/1' }, ['est/2d', 'p/3'], 'ChangeSource')
     expect(props).toHaveLength(2)
     expect(props[0].change).toEqual({ kind: 'reestimate', issue: 2, estimate: 'est/5d' })
-    expect(describeChange(props[0].plan)).toBe('est/2d → est/5d')
+    expect(props[0].summary).toBe('est/2d → est/5d')
     expect(props[1].change).toEqual({ kind: 'reprioritize', issue: 2, priority: 'p/1' })
     expect(props[0].issueTitle).toBe('ChangeSource')
   })
 
+  it('proposes an assignment only when it differs from the current assignee', () => {
+    const change = proposalsFor({ issue: 2, assignee: 'christian' }, [], undefined, { currentAssignee: null })
+    expect(change).toHaveLength(1)
+    expect(change[0].change).toEqual({ kind: 'assign', issue: 2, assignee: 'christian' })
+    expect(change[0].summary).toBe('assign → @christian')
+    expect(change[0].plan).toBeUndefined()
+    // already assigned → no proposal
+    expect(proposalsFor({ issue: 2, assignee: 'christian' }, [], undefined, { currentAssignee: 'christian' })).toEqual([])
+  })
+
+  it('proposes a milestone move, labeled from the milestones list, skipping a no-op', () => {
+    const ctx = { currentMilestoneId: 1, milestones: [{ id: 3, title: 'P5 — Dogfood' }] }
+    const props = proposalsFor({ issue: 2, milestone: 3 }, [], undefined, ctx)
+    expect(props).toHaveLength(1)
+    expect(props[0].change).toEqual({ kind: 'remilestone', issue: 2, milestone: 3, milestoneTitle: 'P5 — Dogfood' })
+    expect(props[0].summary).toBe('milestone → P5 — Dogfood')
+    // same milestone → no proposal
+    expect(proposalsFor({ issue: 2, milestone: 1 }, [], undefined, ctx)).toEqual([])
+  })
+
   it('drops a noop axis (already at the requested value)', () => {
     const props = proposalsFor({ issue: 2, estimate: 'est/2d', priority: 'p/1' }, ['est/2d', 'p/3'])
     expect(props.map((p) => p.change.kind)).toEqual(['reprioritize']) // estimate unchanged
diff --git a/packages/core/src/changes/apply-changes-v0.ts b/packages/core/src/changes/apply-changes-v0.ts
index 2f705d9..2efbe0a 100644
--- a/packages/core/src/changes/apply-changes-v0.ts
+++ b/packages/core/src/changes/apply-changes-v0.ts
@@ -90,18 +90,32 @@ export function summarizeChange(change: IssueChange, currentLabels: string[] = [
   }
 }
 
-/** A change the agent proposes: the concrete op + its diff, ready for approve-then-apply. */
+/** A change the agent proposes: the concrete op + its human diff, ready for approve-then-apply. */
 export interface ChangeProposal {
   change: IssueChange
-  plan: LabelPlan
+  /** One-line diff for the approve UI — always present ({@link summarizeChange}). */
+  summary: string
+  /** The label plan, for label kinds only (absent for assign/milestone). */
+  plan?: LabelPlan
   issueTitle?: string
 }
 
-/** What the `propose_change` tool accepts — a target issue and the axes to set. */
+/** What the `propose_change` tool accepts — a target issue and the fields to set. */
 export interface ProposeChangeArgs {
   issue: number
   estimate?: EstimateLabel
   priority?: PriorityLabel
+  /** Login to assign, or null to unassign. Omit to leave assignee untouched. */
+  assignee?: string | null
+  /** Milestone id to set, or null to clear. Omit to leave the milestone untouched. */
+  milestone?: number | null
+}
+
+/** Current state + lookups a proposal needs to skip noops and label the milestone. */
+export interface ProposalContext {
+  currentAssignee?: string | null
+  currentMilestoneId?: number | null
+  milestones?: { id: number; title: string }[]
 }
 
 function isEstimate(v: unknown): v is EstimateLabel {
@@ -112,25 +126,33 @@ function isPriority(v: unknown): v is PriorityLabel {
 }
 
 /**
- * Build the concrete, non-noop proposals for a `propose_change` request against
- * an issue's current labels. Invalid or unchanged axes are dropped — the agent
- * proposes only real changes, and never a label outside the est/* · p/* axes.
+ * Build the concrete, non-noop proposals for a `propose_change` request. Label
+ * axes (est/*, p/*) are validated and never invented; assign/milestone are
+ * emitted only when they differ from the issue's current value (via `ctx`). Each
+ * proposal carries a human `summary`; label kinds also carry the label plan.
  */
 export function proposalsFor(
   args: ProposeChangeArgs,
   currentLabels: string[],
   issueTitle?: string,
+  ctx: ProposalContext = {},
 ): ChangeProposal[] {
   const out: ChangeProposal[] = []
-  if (isEstimate(args.estimate)) {
-    const change: IssueChange = { kind: 'reestimate', issue: args.issue, estimate: args.estimate }
+  const pushLabel = (change: LabelChange) => {
     const plan = planIssueChange(currentLabels, change)
-    if (!plan.noop) out.push({ change, plan, issueTitle })
+    if (!plan.noop) out.push({ change, plan, summary: describeChange(plan), issueTitle })
   }
-  if (isPriority(args.priority)) {
-    const change: IssueChange = { kind: 'reprioritize', issue: args.issue, priority: args.priority }
-    const plan = planIssueChange(currentLabels, change)
-    if (!plan.noop) out.push({ change, plan, issueTitle })
+  if (isEstimate(args.estimate)) pushLabel({ kind: 'reestimate', issue: args.issue, estimate: args.estimate })
+  if (isPriority(args.priority)) pushLabel({ kind: 'reprioritize', issue: args.issue, priority: args.priority })
+
+  if (args.assignee !== undefined && args.assignee !== (ctx.currentAssignee ?? null)) {
+    const change: IssueChange = { kind: 'assign', issue: args.issue, assignee: args.assignee }
+    out.push({ change, summary: summarizeChange(change), issueTitle })
+  }
+  if (args.milestone !== undefined && args.milestone !== (ctx.currentMilestoneId ?? null)) {
+    const milestoneTitle = ctx.milestones?.find((m) => m.id === args.milestone)?.title ?? null
+    const change: IssueChange = { kind: 'remilestone', issue: args.issue, milestone: args.milestone, milestoneTitle }
+    out.push({ change, summary: summarizeChange(change), issueTitle })
   }
   return out
 }
diff --git a/packages/core/src/gitea/client.test.ts b/packages/core/src/gitea/client.test.ts
index 935372a..aa92ccb 100644
--- a/packages/core/src/gitea/client.test.ts
+++ b/packages/core/src/gitea/client.test.ts
@@ -146,6 +146,22 @@ describe('createGiteaClient.getIssue', () => {
     ])
   })
 
+  it('listCollaborators maps login+name and prepends the owner when absent', async () => {
+    const { fetch } = stubFetch([{ login: 'stephen', full_name: 'Stephen M.' }])
+    const people = await createGiteaClient(CONFIG, fetch).listCollaborators()
+    // owner (christian) prepended since /collaborators omits them; collaborator name preserved
+    expect(people).toEqual([
+      { login: 'christian', name: 'christian' },
+      { login: 'stephen', name: 'Stephen M.' },
+    ])
+  })
+
+  it('listCollaborators does not double-add the owner when already listed', async () => {
+    const { fetch } = stubFetch([{ login: 'christian', full_name: 'Christian L.' }])
+    const people = await createGiteaClient(CONFIG, fetch).listCollaborators()
+    expect(people).toEqual([{ login: 'christian', name: 'Christian L.' }])
+  })
+
   it('getFile returns null on 404 and content+sha on hit', async () => {
     const miss = stubFetch('nope', 404)
     expect(await createGiteaClient(CONFIG, miss.fetch).getFile('directives/log.jsonl')).toBeNull()
diff --git a/packages/core/src/gitea/client.ts b/packages/core/src/gitea/client.ts
index b2260e1..63e4c68 100644
--- a/packages/core/src/gitea/client.ts
+++ b/packages/core/src/gitea/client.ts
@@ -101,6 +101,8 @@ export interface GiteaClient {
   getIssueTimeline(index: number): Promise<LifecycleEvent[]>
   /** Every label defined on the repo (id + name), for name→id resolution. */
   listLabels(): Promise<GiteaLabel[]>
+  /** Repo collaborators (login + display name) — the assignable people. */
+  listCollaborators(): Promise<{ login: string; name: string }[]>
   /** Replace an issue's entire label set with the given label ids. Write. */
   setIssueLabels(index: number, labelIds: number[]): Promise<void>
   /** Replace an issue's assignees (empty array unassigns); returns the updated issue. Write. */
@@ -233,6 +235,19 @@ export function createGiteaClient(config: GiteaConfig, fetchImpl: FetchLike): Gi
       await request(`/issues/${index}/labels`, { method: 'PUT', body: { labels: labelIds } })
     },
 
+    async listCollaborators() {
+      const raw = await requestAll<{ login: string; full_name?: string }>(
+        (page) => `/collaborators?page=${page}&limit=${PAGE_LIMIT}`,
+      )
+      const collabs = raw.map((u) => ({ login: u.login, name: u.full_name || u.login }))
+      // The owner is assignable but is not returned by /collaborators — prepend them
+      // so a solo-owner repo still has an assignable person.
+      if (!collabs.some((c) => c.login === config.owner)) {
+        collabs.unshift({ login: config.owner, name: config.owner })
+      }
+      return collabs
+    },
+
     async setIssueAssignees(index, logins) {
       const raw = (await request(`/issues/${index}`, { method: 'PATCH', body: { assignees: logins } })) as RawIssue
       return normalizeIssue(raw)
diff --git a/packages/core/src/index.ts b/packages/core/src/index.ts
index 7f3a3d3..e73de28 100644
--- a/packages/core/src/index.ts
+++ b/packages/core/src/index.ts
@@ -24,7 +24,14 @@ export type {
 } from './gitea/types.js'
 
 export { describeChange, isLabelChange, planIssueChange, proposalsFor, summarizeChange } from './changes/apply-changes-v0.js'
-export type { ChangeProposal, IssueChange, LabelChange, LabelPlan, ProposeChangeArgs } from './changes/apply-changes-v0.js'
+export type {
+  ChangeProposal,
+  IssueChange,
+  LabelChange,
+  LabelPlan,
+  ProposalContext,
+  ProposeChangeArgs,
+} from './changes/apply-changes-v0.js'
 
 export {
   inferColumnV0,